Formation of the Knightly Korčak Clan and the Politics of Kinship of the Przemyśl Magnates of Ruthenian Origin in the Fifteenth Century - Zazuljak, Jurìj (. Litauen und Ruthenien. - Wiesbaden : Harrassowitz, 2007. - 364 S.. - Ill.. - ISBN 978-3-447-05605-2, 2007)